Without limiting the scope of the invention, its background is described in connection with the extraction of commercially important compounds including lipids from algal cultures.
U.S. Pat. No. 4,341,038 issued to Bloch et al. (1982) relates to the cultivation and harvesting of halophile algae, especially of the Dunaliella type, and to a process for the recovery from such algae of oil products useful as a source of energy, specifically as fuel or as a chemical feedstock. According to the '038 patent oil products and a high nitrogen content residue are obtained by growing halophilic algae in saline solution, harvesting an algae-salt water slurry, solvent extracting said slurry, and recovering the product and residue. Use of a growth promoting enzyme, salt concentration gradients for harvesting, and water insoluble solvents at elevated temperatures are preferred.
U.S. Pat. No. 6,805,800 issued to Keating (2004) describes a method of recovering fat soluble compounds, including but not restricted to pigments such as beta-carotene, from solutions, including but not restricted to those solutions containing microalgal cells. According to the Keating patent, the method comprises passing a solution containing a fat soluble compound is passed through a fluidized bed of crystalline metallic ore particles, such as magnetite, allowing the fat soluble compound to bind to the particles to form a complex. The fat soluble compound is released from the complex by passing a wash solution through the fluidized bed and is subsequently collected in the solution.